I'm not sure that many of the internal IBM groups enforce approvals prior to execution.  The approval prior to execution does make audits easier if that is a requirement for your organization.  Overall getting peer reviewers for scripts and test cases is an overhead burden that must be included in your test group's ability to churn out more test cases and scripts as the review process adds significant ceremony and overhead time spent to the process.

Things to consider when determining your test process:
1. Is it a business requirement to have mandatory reviews and audit trails for all tests executed?
2. Is test coverage of all requirements more important than "deep" testing of complex features?
3. Is my test team experienced enough to maximize individual testing output or are peer reviews and test strategy sessions needed to get the desired testing results?
4. How much if any of my testing effort should be strategically directed towards areas of high defect density or new complexity to reduce overall risk?
5. Are my requirements specified with enough completeness and detail to test them as they are OR do I have to spend testing resources to get requirements elicited to a testable level?
6. What set of test environment factors must be covered and what strategy do I employ?

Once you have gauged what amount of testing resources you have to do your testing and how much testing has to be done, then you can choose your testing process in terms of its formality and the associated overhead cost.  Few organizations impose a strict process unless there is an industry mandate for it as there are never enough resources to test all that you need to test.

I realize that I failed to answer the question about testing approvals being batched, but it is really not a very important question as each approver gets notified of each approval request.  It goes in your work queue and you whittle them down as a pile on the days that you decide to take time out to do approvals.  Batching them up and holding a meeting is just not an efficient way to handle them.  It should be a background task that fits the approver's schedule and left with a date due and overdue reminder notices to get it cleaned up across a set of items.  At some point a team lead will have to send reminders to clean up approvals for a given milestone but otherwise it shouldn't be a team meeting activity requiring batching.  Obviously this is just my opinion and is colored by my experience with test teams having experienced and disciplined team members.